| Message ID | 20220420164836.1181-5-shameerali.kolothum.thodi@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ACPI/IORT: Support for IORT RMR node | expand |
On Wed, Apr 20, 2022 at 05:48:31PM +0100, Shameer Kolothum wrote: > Parse through the IORT RMR nodes and populate the reserve region list > corresponding to a given IOMMU and device(optional). Also, go through > the ID mappings of the RMR node and retrieve all the SIDs associated > with it. > > Also make sure we update generic_iommu_put_resv_regions() with > resv_region_free_fw_data() callback to free up any RMR related > memory allocation. > > [Lorenzo: For ACPI IORT] > Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Tested-by: Steven Price <steven.price@arm.com> > Tested-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> > Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> > --- > drivers/acpi/arm64/iort.c | 264 ++++++++++++++++++++++++++++++++++++++ > drivers/iommu/iommu.c | 12 +- > 2 files changed, 272 insertions(+), 4 deletions(-) > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > index cd5d1d7823cb..8b189e9eca95 100644 > --- a/drivers/acpi/arm64/iort.c > +++ b/drivers/acpi/arm64/iort.c > @@ -788,6 +788,267 @@ void acpi_configure_pmsi_domain(struct device *dev) > } > > #ifdef CONFIG_IOMMU_API > +static void iort_rmr_free_fw_data(struct device *dev, > + struct iommu_resv_region *region) > +{ > + kfree(region->fw_data.rmr.sids); > +} > + > +static void iort_rmr_desc_check_overlap(struct acpi_iort_rmr_desc *desc, > + u32 count) > +{ > + int i, j; > + > + for (i = 0; i < count; i++) { > + u64 end, start = desc[i].base_address, length = desc[i].length; > + > + if (!length) { > + pr_err(FW_BUG "RMR descriptor[0x%llx] with zero length, continue anyway\n", > + start); > + continue; > + } > + > + end = start + length - 1; > + > + /* Check for address overlap */ > + for (j = i + 1; j < count; j++) { > + u64 e_start = desc[j].base_address; > + u64 e_end = e_start + desc[j].length - 1; > + > + if (start <= e_end && end >= e_start) > + pr_err(FW_BUG "RMR descriptor[0x%llx - 0x%llx] overlaps, continue anyway\n", > + start, end); > + } > + } > +} > + > +/* > + * Please note, we will keep the already allocated RMR reserve > + * regions in case of a memory allocation failure. > + */ > +static void iort_get_rmrs(struct acpi_iort_node *node, > + struct acpi_iort_node *smmu, > + u32 *sids, u32 num_sids, > + struct list_head *head) > +{ > + struct acpi_iort_rmr *rmr = (struct acpi_iort_rmr *)node->node_data; > + struct acpi_iort_rmr_desc *rmr_desc; > + int i; > + > + rmr_desc = ACPI_ADD_PTR(struct acpi_iort_rmr_desc, node, > + rmr->rmr_offset); > + > + iort_rmr_desc_check_overlap(rmr_desc, rmr->rmr_count); > + > + for (i = 0; i < rmr->rmr_count; i++, rmr_desc++) { > + struct iommu_resv_region *region; > + enum iommu_resv_type type; > + u32 *sids_copy; > + int prot = IOMMU_READ | IOMMU_WRITE; > + u64 addr = rmr_desc->base_address, size = rmr_desc->length; > + > + if (!IS_ALIGNED(addr, SZ_64K) || !IS_ALIGNED(size, SZ_64K)) { > + /* PAGE align base addr and size */ > + addr &= PAGE_MASK; > + size = PAGE_ALIGN(size + offset_in_page(rmr_desc->base_address)); > + > + pr_err(FW_BUG "RMR descriptor[0x%llx - 0x%llx] not aligned to 64K, continue with [0x%llx - 0x%llx]\n", > + rmr_desc->base_address, > + rmr_desc->base_address + rmr_desc->length - 1, > + addr, addr + size - 1); > + } > + > + if (rmr->flags & ACPI_IORT_RMR_REMAP_PERMITTED) > + type = IOMMU_RESV_DIRECT_RELAXABLE; > + else > + type = IOMMU_RESV_DIRECT; > + > + if (rmr->flags & ACPI_IORT_RMR_ACCESS_PRIVILEGE) > + prot |= IOMMU_PRIV; > + > + /* Attributes 0x00 - 0x03 represents device memory */ > + if (ACPI_IORT_RMR_ACCESS_ATTRIBUTES(rmr->flags) <= > + ACPI_IORT_RMR_ATTR_DEVICE_GRE) > + prot |= IOMMU_MMIO; > + else if (ACPI_IORT_RMR_ACCESS_ATTRIBUTES(rmr->flags) == > + ACPI_IORT_RMR_ATTR_NORMAL_IWB_OWB) > + prot |= IOMMU_CACHE; > + > + /* Create a copy of SIDs array to associate with this resv region */ > + sids_copy = kmemdup(sids, num_sids * sizeof(*sids), GFP_KERNEL); > + if (!sids_copy) > + return; > + > + region = iommu_alloc_resv_region(addr, size, prot, type); > + if (!region) { > + kfree(sids_copy); > + return; > + } > + > + region->fw_data.rmr.sids = sids_copy; > + region->fw_data.rmr.num_sids = num_sids; > + region->resv_region_free_fw_data = iort_rmr_free_fw_data; > + list_add_tail(®ion->list, head); > + } > +} > + > +static u32 *iort_rmr_alloc_sids(u32 *sids, u32 count, u32 id_start, > + u32 new_count) > +{ > + u32 *new_sids; > + u32 total_count = count + new_count; > + int i; > + > + new_sids = krealloc_array(sids, count + new_count, > + sizeof(*new_sids), GFP_KERNEL); > + if (!new_sids) > + return NULL; > + > + for (i = count; i < total_count; i++) > + new_sids[i] = id_start++; > + > + return new_sids; > +} > + > +static bool iort_rmr_has_dev(struct device *dev, u32 id_start, > + u32 id_count) > +{ > + int i; > + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); > + > + /* > + * Make sure the kernel has preserved the boot firmware PCIe > + * configuration. This is required to ensure that the RMR PCIe > + * StreamIDs are still valid (Refer: ARM DEN 0049E.d Section 3.1.1.5). > + */ > + if (dev_is_pci(dev)) { > + struct pci_dev *pdev = to_pci_dev(dev); > + struct pci_host_bridge *host = pci_find_host_bridge(pdev->bus); > + > + if (!host->preserve_config) > + return false; > + } > + > + for (i = 0; i < fwspec->num_ids; i++) { > + if (fwspec->ids[i] >= id_start && > + fwspec->ids[i] <= id_start + id_count) > + return true; > + } > + > + return false; > +} > + > +static void iort_node_get_rmr_info(struct acpi_iort_node *node, > + struct acpi_iort_node *iommu, > + struct device *dev, struct list_head *head) > +{ > + struct acpi_iort_node *smmu = NULL; > + struct acpi_iort_rmr *rmr; > + struct acpi_iort_id_mapping *map; > + u32 *sids = NULL; > + u32 num_sids = 0; > + int i; > + > + if (!node->mapping_offset || !node->mapping_count) { > + pr_err(FW_BUG "Invalid ID mapping, skipping RMR node %p\n", > + node); > + return; > + } > + > + rmr = (struct acpi_iort_rmr *)node->node_data; > + if (!rmr->rmr_offset || !rmr->rmr_count) > + return; > + > + map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node, > + node->mapping_offset); > + > + /* > + * Go through the ID mappings and see if we have a match for SMMU > + * and dev(if !NULL). If found, get the sids for the Node. > + * Please note, id_count is equal to the number of IDs in the > + * range minus one. > + */ > + for (i = 0; i < node->mapping_count; i++, map++) { > + struct acpi_iort_node *parent; > + > + if (!map->id_count) > + continue; > + > + parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, > + map->output_reference); > + if (parent != iommu) > + continue; > + > + /* If dev is valid, check RMR node corresponds to the dev SID */ > + if (dev && !iort_rmr_has_dev(dev, map->output_base, > + map->id_count)) > + continue; > + > + /* Retrieve SIDs associated with the Node. */ > + sids = iort_rmr_alloc_sids(sids, num_sids, map->output_base, > + map->id_count + 1); > + if (!sids) > + return; > + > + num_sids += map->id_count + 1; > + } > + > + if (!sids) > + return; > + > + iort_get_rmrs(node, smmu, sids, num_sids, head); > + kfree(sids); > +} > + > +static void iort_find_rmrs(struct acpi_iort_node *iommu, struct device *dev, > + struct list_head *head) > +{ > + struct acpi_table_iort *iort; > + struct acpi_iort_node *iort_node, *iort_end; > + int i; > + > + /* Only supports ARM DEN 0049E.d onwards */ > + if (iort_table->revision < 5) > + return; > + > + iort = (struct acpi_table_iort *)iort_table; > + > + iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort, > + iort->node_offset); > + iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort, > + iort_table->length); > + > + for (i = 0; i < iort->node_count; i++) { > + if (WARN_TAINT(iort_node >= iort_end, TAINT_FIRMWARE_WORKAROUND, > + "IORT node pointer overflows, bad table!\n")) > + return; > + > + if (iort_node->type == ACPI_IORT_NODE_RMR) > + iort_node_get_rmr_info(iort_node, iommu, dev, head); > + > + iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node, > + iort_node->length); > + } > +} > + > +/* > + * Populate the RMR list associated with a given IOMMU and dev(if provided). > + * If dev is NULL, the function populates all the RMRs associated with the > + * given IOMMU. > + */ > +static void iort_iommu_rmr_get_resv_regions(struct fwnode_handle *iommu_fwnode, > + struct device *dev, > + struct list_head *head) > +{ > + struct acpi_iort_node *iommu; > + > + iommu = iort_get_iort_node(iommu_fwnode); > + if (!iommu) > + return; > + > + iort_find_rmrs(iommu, dev, head); > +} > + > static struct acpi_iort_node *iort_get_msi_resv_iommu(struct device *dev) > { > struct acpi_iort_node *iommu; > @@ -868,7 +1129,10 @@ static void iort_iommu_msi_get_resv_regions(struct device *dev, > */ > void iort_iommu_get_resv_regions(struct device *dev, struct list_head *head) > { > + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); > + > iort_iommu_msi_get_resv_regions(dev, head); > + iort_iommu_rmr_get_resv_regions(fwspec->iommu_fwnode, dev, head); > } > > static inline bool iort_iommu_driver_enabled(u8 type) > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index f2c45b85b9fc..4431a7a5da0a 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -2597,16 +2597,20 @@ void iommu_put_resv_regions(struct device *dev, struct list_head *list) > * @list: reserved region list for device > * > * IOMMU drivers can use this to implement their .put_resv_regions() callback > - * for simple reservations. Memory allocated for each reserved region will be > - * freed. If an IOMMU driver allocates additional resources per region, it is > - * going to have to implement a custom callback. > + * for simple reservations. Memory allocated for each reserved region and any > + * associated firmware specific allocations will be freed. If an IOMMU driver > + * allocates additional resources per region, it is going to have to > + * implement a custom callback. > */ > void generic_iommu_put_resv_regions(struct device *dev, struct list_head *list) > { > struct iommu_resv_region *entry, *next; > > - list_for_each_entry_safe(entry, next, list, list) > + list_for_each_entry_safe(entry, next, list, list) { > + if (entry->resv_region_free_fw_data) > + entry->resv_region_free_fw_data(dev, entry); > kfree(entry); I'd move the kfree to the free callback if present. This would also allow to hide the union from the common code entirely and use a container structure like: struct iommu_iort_rmr_data { struct iommu_resv_region rr; /* Stream IDs associated with IORT RMR entry */ const u32 *sids; u32 num_sids; };
> -----Original Message----- > From: Christoph Hellwig [mailto:hch@infradead.org] > Sent: 21 April 2022 07:49 > To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com> > Cc: linux-arm-kernel@lists.infradead.org; linux-acpi@vger.kernel.org; > iommu@lists.linux-foundation.org; Linuxarm <linuxarm@huawei.com>; > lorenzo.pieralisi@arm.com; joro@8bytes.org; robin.murphy@arm.com; > will@kernel.org; wanghuiqiang <wanghuiqiang@huawei.com>; Guohanjun > (Hanjun Guo) <guohanjun@huawei.com>; steven.price@arm.com; > Sami.Mujawar@arm.com; jon@solid-run.com; eric.auger@redhat.com; > laurentiu.tudor@nxp.com; hch@infradead.org > Subject: Re: [PATCH v10 4/9] ACPI/IORT: Add support to retrieve IORT RMR > reserved regions > [...] > > void generic_iommu_put_resv_regions(struct device *dev, struct list_head > *list) > > { > > struct iommu_resv_region *entry, *next; > > > > - list_for_each_entry_safe(entry, next, list, list) > > + list_for_each_entry_safe(entry, next, list, list) { > > + if (entry->resv_region_free_fw_data) > > + entry->resv_region_free_fw_data(dev, entry); > > kfree(entry); > > I'd move the kfree to the free callback if present. This would also > allow to hide the union from the common code entirely and use a > container structure like: > > struct iommu_iort_rmr_data { > struct iommu_resv_region rr; > > /* Stream IDs associated with IORT RMR entry */ > const u32 *sids; > u32 num_sids; > }; Ok. I will respin soon with the above changes. Thanks, Shameer
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index cd5d1d7823cb..8b189e9eca95 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -788,6 +788,267 @@ void acpi_configure_pmsi_domain(struct device *dev) } #ifdef CONFIG_IOMMU_API +static void iort_rmr_free_fw_data(struct device *dev, + struct iommu_resv_region *region) +{ + kfree(region->fw_data.rmr.sids); +} + +static void iort_rmr_desc_check_overlap(struct acpi_iort_rmr_desc *desc, + u32 count) +{ + int i, j; + + for (i = 0; i < count; i++) { + u64 end, start = desc[i].base_address, length = desc[i].length; + + if (!length) { + pr_err(FW_BUG "RMR descriptor[0x%llx] with zero length, continue anyway\n", + start); + continue; + } + + end = start + length - 1; + + /* Check for address overlap */ + for (j = i + 1; j < count; j++) { + u64 e_start = desc[j].base_address; + u64 e_end = e_start + desc[j].length - 1; + + if (start <= e_end && end >= e_start) + pr_err(FW_BUG "RMR descriptor[0x%llx - 0x%llx] overlaps, continue anyway\n", + start, end); + } + } +} + +/* + * Please note, we will keep the already allocated RMR reserve + * regions in case of a memory allocation failure. + */ +static void iort_get_rmrs(struct acpi_iort_node *node, + struct acpi_iort_node *smmu, + u32 *sids, u32 num_sids, + struct list_head *head) +{ + struct acpi_iort_rmr *rmr = (struct acpi_iort_rmr *)node->node_data; + struct acpi_iort_rmr_desc *rmr_desc; + int i; + + rmr_desc = ACPI_ADD_PTR(struct acpi_iort_rmr_desc, node, + rmr->rmr_offset); + + iort_rmr_desc_check_overlap(rmr_desc, rmr->rmr_count); + + for (i = 0; i < rmr->rmr_count; i++, rmr_desc++) { + struct iommu_resv_region *region; + enum iommu_resv_type type; + u32 *sids_copy; + int prot = IOMMU_READ | IOMMU_WRITE; + u64 addr = rmr_desc->base_address, size = rmr_desc->length; + + if (!IS_ALIGNED(addr, SZ_64K) || !IS_ALIGNED(size, SZ_64K)) { + /* PAGE align base addr and size */ + addr &= PAGE_MASK; + size = PAGE_ALIGN(size + offset_in_page(rmr_desc->base_address)); + + pr_err(FW_BUG "RMR descriptor[0x%llx - 0x%llx] not aligned to 64K, continue with [0x%llx - 0x%llx]\n", + rmr_desc->base_address, + rmr_desc->base_address + rmr_desc->length - 1, + addr, addr + size - 1); + } + + if (rmr->flags & ACPI_IORT_RMR_REMAP_PERMITTED) + type = IOMMU_RESV_DIRECT_RELAXABLE; + else + type = IOMMU_RESV_DIRECT; + + if (rmr->flags & ACPI_IORT_RMR_ACCESS_PRIVILEGE) + prot |= IOMMU_PRIV; + + /* Attributes 0x00 - 0x03 represents device memory */ + if (ACPI_IORT_RMR_ACCESS_ATTRIBUTES(rmr->flags) <= + ACPI_IORT_RMR_ATTR_DEVICE_GRE) + prot |= IOMMU_MMIO; + else if (ACPI_IORT_RMR_ACCESS_ATTRIBUTES(rmr->flags) == + ACPI_IORT_RMR_ATTR_NORMAL_IWB_OWB) + prot |= IOMMU_CACHE; + + /* Create a copy of SIDs array to associate with this resv region */ + sids_copy = kmemdup(sids, num_sids * sizeof(*sids), GFP_KERNEL); + if (!sids_copy) + return; + + region = iommu_alloc_resv_region(addr, size, prot, type); + if (!region) { + kfree(sids_copy); + return; + } + + region->fw_data.rmr.sids = sids_copy; + region->fw_data.rmr.num_sids = num_sids; + region->resv_region_free_fw_data = iort_rmr_free_fw_data; + list_add_tail(®ion->list, head); + } +} + +static u32 *iort_rmr_alloc_sids(u32 *sids, u32 count, u32 id_start, + u32 new_count) +{ + u32 *new_sids; + u32 total_count = count + new_count; + int i; + + new_sids = krealloc_array(sids, count + new_count, + sizeof(*new_sids), GFP_KERNEL); + if (!new_sids) + return NULL; + + for (i = count; i < total_count; i++) + new_sids[i] = id_start++; + + return new_sids; +} + +static bool iort_rmr_has_dev(struct device *dev, u32 id_start, + u32 id_count) +{ + int i; + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + + /* + * Make sure the kernel has preserved the boot firmware PCIe + * configuration. This is required to ensure that the RMR PCIe + * StreamIDs are still valid (Refer: ARM DEN 0049E.d Section 3.1.1.5). + */ + if (dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_host_bridge *host = pci_find_host_bridge(pdev->bus); + + if (!host->preserve_config) + return false; + } + + for (i = 0; i < fwspec->num_ids; i++) { + if (fwspec->ids[i] >= id_start && + fwspec->ids[i] <= id_start + id_count) + return true; + } + + return false; +} + +static void iort_node_get_rmr_info(struct acpi_iort_node *node, + struct acpi_iort_node *iommu, + struct device *dev, struct list_head *head) +{ + struct acpi_iort_node *smmu = NULL; + struct acpi_iort_rmr *rmr; + struct acpi_iort_id_mapping *map; + u32 *sids = NULL; + u32 num_sids = 0; + int i; + + if (!node->mapping_offset || !node->mapping_count) { + pr_err(FW_BUG "Invalid ID mapping, skipping RMR node %p\n", + node); + return; + } + + rmr = (struct acpi_iort_rmr *)node->node_data; + if (!rmr->rmr_offset || !rmr->rmr_count) + return; + + map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node, + node->mapping_offset); + + /* + * Go through the ID mappings and see if we have a match for SMMU + * and dev(if !NULL). If found, get the sids for the Node. + * Please note, id_count is equal to the number of IDs in the + * range minus one. + */ + for (i = 0; i < node->mapping_count; i++, map++) { + struct acpi_iort_node *parent; + + if (!map->id_count) + continue; + + parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table, + map->output_reference); + if (parent != iommu) + continue; + + /* If dev is valid, check RMR node corresponds to the dev SID */ + if (dev && !iort_rmr_has_dev(dev, map->output_base, + map->id_count)) + continue; + + /* Retrieve SIDs associated with the Node. */ + sids = iort_rmr_alloc_sids(sids, num_sids, map->output_base, + map->id_count + 1); + if (!sids) + return; + + num_sids += map->id_count + 1; + } + + if (!sids) + return; + + iort_get_rmrs(node, smmu, sids, num_sids, head); + kfree(sids); +} + +static void iort_find_rmrs(struct acpi_iort_node *iommu, struct device *dev, + struct list_head *head) +{ + struct acpi_table_iort *iort; + struct acpi_iort_node *iort_node, *iort_end; + int i; + + /* Only supports ARM DEN 0049E.d onwards */ + if (iort_table->revision < 5) + return; + + iort = (struct acpi_table_iort *)iort_table; + + iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort, + iort->node_offset); + iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort, + iort_table->length); + + for (i = 0; i < iort->node_count; i++) { + if (WARN_TAINT(iort_node >= iort_end, TAINT_FIRMWARE_WORKAROUND, + "IORT node pointer overflows, bad table!\n")) + return; + + if (iort_node->type == ACPI_IORT_NODE_RMR) + iort_node_get_rmr_info(iort_node, iommu, dev, head); + + iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node, + iort_node->length); + } +} + +/* + * Populate the RMR list associated with a given IOMMU and dev(if provided). + * If dev is NULL, the function populates all the RMRs associated with the + * given IOMMU. + */ +static void iort_iommu_rmr_get_resv_regions(struct fwnode_handle *iommu_fwnode, + struct device *dev, + struct list_head *head) +{ + struct acpi_iort_node *iommu; + + iommu = iort_get_iort_node(iommu_fwnode); + if (!iommu) + return; + + iort_find_rmrs(iommu, dev, head); +} + static struct acpi_iort_node *iort_get_msi_resv_iommu(struct device *dev) { struct acpi_iort_node *iommu; @@ -868,7 +1129,10 @@ static void iort_iommu_msi_get_resv_regions(struct device *dev, */ void iort_iommu_get_resv_regions(struct device *dev, struct list_head *head) { + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + iort_iommu_msi_get_resv_regions(dev, head); + iort_iommu_rmr_get_resv_regions(fwspec->iommu_fwnode, dev, head); } static inline bool iort_iommu_driver_enabled(u8 type) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index f2c45b85b9fc..4431a7a5da0a 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2597,16 +2597,20 @@ void iommu_put_resv_regions(struct device *dev, struct list_head *list) * @list: reserved region list for device * * IOMMU drivers can use this to implement their .put_resv_regions() callback - * for simple reservations. Memory allocated for each reserved region will be - * freed. If an IOMMU driver allocates additional resources per region, it is - * going to have to implement a custom callback. + * for simple reservations. Memory allocated for each reserved region and any + * associated firmware specific allocations will be freed. If an IOMMU driver + * allocates additional resources per region, it is going to have to + * implement a custom callback. */ void generic_iommu_put_resv_regions(struct device *dev, struct list_head *list) { struct iommu_resv_region *entry, *next; - list_for_each_entry_safe(entry, next, list, list) + list_for_each_entry_safe(entry, next, list, list) { + if (entry->resv_region_free_fw_data) + entry->resv_region_free_fw_data(dev, entry); kfree(entry); + } } EXPORT_SYMBOL(generic_iommu_put_resv_regions);